I'm torn between calling this an MP custom or a Classics. It's built on an MP Prime base, but it's scale is closer to that of the Classics figures.
The original figure had the dual alt modes of an aircraft carrier and a small fighter jet, but in the show he was depicted as being a huge space carrier. That's what I was going for here.
I'm still working out how the rear deck will transform. For now it's sort of a big collar, but I might make it fold down into tail fins or just onto his back.
I've left the tops of the backs of his legs/ tops of the spaceship open for now in case I need to do something in there. It lets you see a bit of how I put together solid shapes. Here's I've globbed in a lot of Bondo abd fast steel putty to reinforce the shape.

UPDATES are on PAGE 5

Still got a long way to go, but I'm close to having the structure worked out. Once I've got how I'm going to do the conning tower, I can move on to fleshing out the details.

Thanks! I feel pretty confident that I can whip up the necessary bits and pieces for the conning tower and such. Truth be told, I never thought much of Tidalwave's alt mode(s). They don't really look much like real ships. That was my problem with the entire Armada line. Everything was designed from the robot mode first and squeezed into the alt modes. That's why you got things like trucks and helicopters with robot arms hanging off them.
I'm sorry. I went off on a little thing there.
Thanks again.